Field of the Invention
The present invention relates to an automotive headlamp module and, more particularly, to a module used at a low cost by simplifying components thereof and that implements a beam pattern in a low-beam mode when a fail-safe function is performed due to breakdown in a high-beam mode or an adaptive driving-beam mode.
Description of the Related Art
Generally, beam patterns formed by automotive headlamp modules are classified into a low-beam mode, a high-beam mode, and an adaptive driving-beam (e.g., ADB) mode. For example, the ADB mode, automatically adjusts the direction and angle of light based on the driving conditions, and is a technology that automatically adjusts into a high-beam mode and a low-beam mode by sensing a vehicle ahead using a an imaging device. Further, when another vehicle is disposed ahead of the vehicle, the ADB mode enables a driver to comfortably drive without blinding the driver by the light of an approaching vehicle.
A headlamp module of the related art, as show in FIGS. 1 and 2, includes a shield housing 1, a drum type shield 2 rotatably disposed within the shield housing 1, a shield motor 3 that produces power for operating the shield 2, a power transmission gear 4 that transmits power from the shield motor 3 to the shield 2, a PCB (Printed Circuit Board) 5 that has operates of the shield motor 3, a reflector 6 coupled to the shield housing 1, a light source 7 disposed on the reflector 6, an exterior case 8 that fixes the shield housing 1 and the reflector 6, and a case motor 9 coupled to the exterior case 8.
The shield 2 includes a high-beam protrusion 2a, a low-beam protrusion 2b, and an ADB protrusion 2c that protrudes radially. For example, when the shield 2 is rotated and the high-beam protrusion 2a is disposed ahead of the light source 7, a beam pattern of the high-beam mode is implemented. When the low-beam protrusion 2b is disposed ahead of the light source 7, a beam pattern of the low-beam mode is implemented. Further when the ADB protrusion 2c is disposed ahead of the light source 7, a beam pattern of the ADB mode is implemented.
The shield motor 3, is not a common direct current (e.g., DC) motor, but a stepping motor, that accurately adjusts a rotational angle of the shield 2, but has a disadvantage of high price. Moreover, a specific sensor 10 to detect a rotational position and a complex control logic is required, thereby making implementation difficult in common low-cost vehicles.
The case motor 9 is an Intelligent Smart Motor (ISM) that preforms a fail-safe function and the beam pattern in the high-beam mode or the ADB mode is higher than the beam pattern in the low-beam mode. For example, when a problem occurs with the shield motor 3 or the headlamp, the driver of an approaching vehicle may have their field of vision impacted thus potentially contributing to an accident. In other words, the case motor 9 is an ISM motor that communicates to recognize a breakdown mode. Upon recognition of a breakdown mode, the motor rotates the exterior case 8 to rotate the shield housing 1 and the reflector 6 coupled to the exterior case 8 downward, thereby adjusting the beam pattern from the headlamp to be lowered to the ground. However, when the headlamp module of the related art performs a fail-safe function in the high-beam mode or the ADB mode, the beam pattern in the high-beam mode or the beam pattern of the ADB mode is the beam pattern in the fail-safe mode.
Further, the beam pattern in the fail-safe mode does not cross over a cutoff line of a low beam, therefore the beam pattern in a fail-safe mode in the related art is formed in a downward direction substantially proximate to the ground. Additionally, performance deteriorates compared to a low beam state, thereby reducing safety during operation of the vehicle. When the beam pattern in the fail-safe mode crosses over the cutoff line of a low beam, the beam pattern becomes the same as the high-beam mode state, in which the driver's field of vision in an approaching vehicle is impacted. For example, FIG. 2 shows an exemplary beam pattern B1 in a high-beam mode, an exemplary beam pattern B2 in a fail-safe mode in a high-beam state, and an exemplary beam pattern B3 in a low-beam mode. The beam pattern B2 in the fail-safe mode is radiated lower than the beam pattern B3 in the low-beam mode, causing visual range of a driver to be significantly impacted and reduced.
The foregoing is intended merely to aid in the understanding of the background of the present invention, and is not intended to mean that the present invention falls within the purview of the related art that is already known to those skilled in the art.